The goal of this application is to develop a culturally and linguistically appropriate mental health assessment instrument designed to assess outcome of treatment for Spanish-speaking mental health and substance abuse service recipients. Culturally and linguistically appropriate outcome measures are especially needed to determine the presence and direction of health disparities, and to assess quality and outcomes of treatment among minority populations. The proposed research will accomplish this by adapting, translating and field testing and validating the revised Behavior and Symptom Identification Scale (BASIS-R) for use among Spanish speakers from three Spanish-speaking regions: Puerto Rico, Mexico and The Dominican Republic. Under a currently funded project (R01 MH58240) an extensive revision of the BASIS-32, a widely used consumer self-report mental health status measure, was undertaken. This application extends the currently funded work by adapting and translating the instrument for Spanish-speaking Latinos in the U.S. and Puerto Rico, and by allowing for culture-specific modules to be added to the core instrument. Specific aims are to: adapt and translate the instrument into Spanish; identify symptom and functioning domains and items that are culturally relevant to Spanish-speaking Latinos but are not included in the English version of the instrument; field test the adapted/translated instrument; and assess data quality, factor structure reliability, validity, differential item functioning and sensitivity to change for the Spanish instrument. These goals will be accomplished by using the best established methods to develop a preliminary translation. To assess content and semantic equivalence we will conduct focus groups and cognitive interviews. Analysis of the results will be used to further refine the translation for field testing. To assess technical equivalence, we will use the same format, and layout for the Spanish adaptation of the instrument as for the English. The field test of the instrument will enroll a total sample of 600 Latinos: 100 inpatients and 100 outpatients receiving treatment at each of three participating sites in Boston, Puerto Rico and Fresno. To assess criterion and conceptual equivalence, field test data will be used to assess reliability and validity of the instrument. Item Response Theory will be used to assess differential item functioning of the Spanish and English instruments. The instrument developed from this research will provide an important tool for assessing outcomes of mental health treatment among the Latino population.